Such indicating lights have, in general terms, a number of different indicating functions, and tend to be grouped together to constitute multi-function indicating light units. Such functions may for example be those of a reversing light, a direction indicating light, a stop light for indicating that the brakes of the vehicle have been applied, and a fog light, in particular a rear fog light.
Current standards specify a colour for each of these functions when the indicating light is lit. Thus a multi-function indicator light must be arranged to emit light beams of different colours. On the other hand, styling designers tend to require indicator lights to have as uniform an appearance as possible when the light is extinguished. Thus, more generally, it is desirable to be able to provide an indicator light having an appearance (especially in regard to its colour) when extinguished which is different from its appearance when lit.
In order to respond to these opposed requirements, the company VALEO VISION has proposed indicator lights in which the general colour when extinguished is different from the colour of the light beam emitted by the indicator light when the latter is lit, these proposals being contained in particular in published French patent specifications Nos. 2 604 240 and 2 718 824.
In those documents, the indicator lights disclosed generally comprise a light source, together with means for recuperating light flux which are adapted to redirect the light flux emitted by the light source in a first direction of the indicator light unit. Also provided is a first screen which comprises optical elements adapted to converge the light beam towards translucent bands carried on a second screen, these translucent bands being arranged in the second screen alternately with colour bands. The second screen can be seen from outside.
Thus the appearance of the indicator lights when extinguished is determined by the coloured bands, while the light emitted by the indicator light is either not coloured at all, or it has a colour which is different from that of the coloured bands of the second screen.